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By H. I. Aaronson, W. L. Winterbottom, G. M. Pound

On the basis of a statistical thermodynamic treatment of the data of smithz2 on the activity of carbon in austenite, a Darken and smith23 deduced that the interaction energy, wy, between carbon atoms occupying nearest-neighboring interstitial sites is repulsive. Aaronson, Domian, and pound 24 (ADP) have applied two different statistical thermodynamic analyses to the same data. One analysis, a composite of the treatments of Darken and Smith,23 Speiser and Spret-nak," and Kaufman, Radcliffe, and Cohen,26 primarily takes account of the positional entropic effects of wy in dilute solutions. The other, due to Lacher 27 and Fowler and Guggenheim," is also applicable to more concentrated solid solutions. The equations which both analyses produce for a,, can be rearranged so that, when In a,, is plotted against the appropriate function of the carbon content of the austenite, the plot will have a slope of unity when the correct value of wy is employed. Since no other constant need be simultaneously evaluated in order to make this determination, ascertaining the most probable value of wy from Smith's data on the bases of these analyses was an elementary problem in least-squares statistics. ADP demonstrated that the wy's obtained from both analyses vary with temperature in a statistically significant manner. McLellan, Gerrard, Horowitz, and sprague 29 (MGHS), on the other hand, have recently made a new statistical thermodynamic study of a,, and have concluded from this study that wy is independent of temperature. The equation which they derived for a,, is: where 0 = ratio of the mole fraction of carbon atoms to that of iron atoms, z = number of sites from which occupancy is excluded by the presence of a carbon atom and the repulsive character of its interaction with nearest-neighboring carbon atoms (z = zb in Ref. 24), and x = a geometric parameter taking account of overlapping of the exclusion shells of nearby carbon atoms. z is 1 when wy = 0 and 13 when wy = Q. For a given value of z there is a definite value of X . In the absence of an equation connecting z and X, MGHS computed geometrically the value of x at several integral values of z; x increases from 0.47 to 8.67 as z is increased from 2 to 5. MGHS fitted Eq. [I] to the a,, data of Ellis, Davidson, and Bodsworth30 at 925° and 1050°C and to the data of smithz2 at 1000°C. Confining z to integral values in the range 4 to 6, and also somewhat restricting AG, the values of z, X, and AG were sought which would minimize the average root mean square percent deviation, D, of the calculated a,, values from those obtained experimentally. Finding that D was almost always smallest when z = 5, they concluded that z is independent of temperature. Since:23, 26 where R = gas constant and T = absolute temperature, and w,, was considered to be similarly invariant, this statement cannot be strictly true. The temperature range employed, however, was small and the interval between the values of z tested was sufficiently large so that the results could still be consistent with a constant The statistical treatment of the a,, data applied by MGHS is clearly quite approximate. Since more than three values of a,, are available at each temperature, z, and X, and AG have actually been over deter mined, rather than underdetermined as their treatment implies. In order to make more complete and exact use of the a,, data, we shall employ the Legendre Method of Least Squares, as described by Whittaker and Robinson. This technique permits conversion of the overdetermined system of equations produced by the substitution into Eq. [I] of the available pairs of a,, and 0 data at a given temperature into an even determined system. Solution of the latter system yields the most probable value of each of the three constants. This procedure will allow a statistically rigorous test to be made of the conclusion drawn by MGHS in respect of the temperature dependence of In order to obtain linear iiequations of conditions" from Eq. [I], the exact values of the three unknown constants are replaced by G/RT = =/RT + y, where z, i, and aG are estimated values of the constants. This allows the conditional equations to be written in the form:'l where fi -f6, i, =/RT) = the right-hand side of Eq. [I] for a given pair of ayi and values. When applied to Eq. [I], these relationships become: The i equations of condition are reduced to three "normal equations" in the manner discussed by Whittaker and Robinson. The normal equations are then solved for a, ß, and y. Both of these operations are most conveniently performed by means of the computer technique of Winterbottom and Gjostein.32 This technique was used iteratively until the value of 0 (the most sensitive of the three correction factors) became 10.01. (Until they became small, a, 8, and y

Jan 1, 1969

By J. E. Hanafee, G. J. London

MANY studies of the deformation behavior of materials under a superimposed hydrostatic pressure have shown that materials brittle at ambient pressure behave in a ductile manner under pressure. Thus, with a metal such as beryllium which possesses relatively low ductility, but otherwise exhibits quite useful physical and mechanical properties, hydrostatic pressure may be particularly useful for both forming beryllium shapes and studying its deformation behavior. In fact, it has been found1"4 that polycrystal-line beryllium in both ingot and powder form appears to behave in a more ductile manner on a macroscopic level in a hydrostatic pressure environment, and it has been suggested2 that this is due to activating a new slip mode. Furthermore, Andrews and Radcliffe5 have found pressure induced nonbasal dislocation activity in hot pressed beryllium. Recently6 it has been shown in "c-axis" compression tests under hydro-static pressures up to 28 kbars that the shear stress needed to cause slip with a Burgers vector out of the basal plane (pyramidal slip) does not change with increasing pressure in beryllium with a purity of some 99.5 pct. This material is equivalent or more pure than the beryllium used in the previous pressure studies. Thus, it appears, as suggested by Inoue et al.,3 that the hydrostatic pressure affects the fracture stress rather than the stress necessary to activate pyramidal slip in beryllium. However, in "c-axis" pressure tests on high purity 12 zone pass beryllium (˜50 ppm total impurities) the macroscopic compression stress needed to cause pyramidal slip was considerably lower than that at ambient pressure.6 It has further been shown that alloying beryllium with nickel and copper in the range 2-5 wt pct also favors the occurrence of pyramidal slip in "c-axis" compression tests,7'8 while lower amounts of nickel and copper do not have significant effects. In the present study the combined effect of hydrostatic pressure and alloying high purity beryllium on the shear stress needed to cause pyramidal slip has been ascertained. A 2.5 wt pct Cu alloy was selected as the first alloy to study as this level of copper did favor pyramidal slip at room pressure. A high purity (12 zone pass) single crystal of beryllium 0.3 by 0.1 by 0.1 in. was cut and polished by an orientation and lapping technique8 so that the top and bottom compression surfaces were parallel and within 3 min of arc to the (0001) plane and the sides parallel to the {l010} and {ll20} planes. In these compression specimens, therefore, the resolved shear stress was nearly zero on both the basal and prism planes, and slip was restricted to pyramidal systems. Analysis of slip traces on the two lateral surfaces served to accurately identify the active slip planes.6'9 The pressure unit was a modified piston-cylinder device fitted with a manganin transducer coil arrangement which continuously monitored and recorded the hydro-static pressure. The load on the specimen was measured by a strain gage load cell which operated entirely within the pressure chamber. This load cell was calibrated before and after each pressure cycle at room pressure in situ and the calibration did not vary more than ±1 pet. These techniques and devices have been previously described in more detail.6 Successively higher compressive stresses were applied to the single crystal under a superimposed hydrostatic pressure until fracture occurred. The strain rate was (4.5 ± 2.0) x 10-6 sec-1 and the average rate of pressure application and release was approximately 0.3 kbars per min. As the load on the specimen was applied by the piston which was used to increase the hydrostatic pressure, the pressure increased during the compression test. This increase ranged from 0.0 to 0.8 kbars, and the maximum hydrostatic pressures are quoted in Fig. 1. The lateral surfaces of the specimen were examined in a light microscope after each pressurization/stress cycle so that the stress at the onset of {1122} pyramidal slip could be ascertained. Post compression height measurements allowed the plastic strain in the specimen to be evaluated to within 0.03 pct. The resulting compression stress-plastic strain curve is shown in Fig. 1 with results of a "c-axis" test on a similar Be-2.5 wt pct Cu single

Jan 1, 1970

By Edward L. Wilson, Keshavan Nair, Ranbir S. Sandhu

In planning and designing of underground excavations and construction, it is of considerable importance that the stresses and displacements in the rock mass subjected to arbitrary sequences of unloading and loading be within allowable limits. For determination of the stress and displacement fields, the usual approach is to treat the rock as an elastic material and to apply the principles of the theory of elasticity. However, analytic solutions are available only for a limited class of problems of simple geometry and idealized material properties. Nonhomogeneity and anisotropy of material coupled with complex geometrical configuration and initial stress fields that are almost always preexistent in rock masses at great depths, render the problem intractable by analytical methods. Approximate solution techniques using numerical procedures have, therefore, to be resorted to. The finite element method as applied to plane stress analysis was introduced by Clough.1 It has developed into a powerful tool for the analysis of various field problems in structural and continuum mechanics. The method is well documented in the literature2-6 and, therefore, its historical development will not be discussed here. Wilson's analysis of the plane stress/strain problem has found extensive use in the area of soil and rock mechanics including stresses around underground openings; stresses and displacements in dams, foundations, etc.7-11 In his analysis of the axisymmetric solid,3 Wilson proposed a procedure to allow for certain cases of nonlinear material properties. In this chapter, the develop-

Jan 1, 1972

By F. W. Jessen, C. C. Patton

Adsorbed films were formed on polished stainless steel specimens from dilute benzene solutions of two crude oil distillation residua. Although the two residua were extremely dissimilar in composition, contact angle measurements showed that the two films increased the wettability of the steel specimens to oil by equal amounts. Furthermore, the wettability of the films was essentially unaffected by the desorption techniques used. Paraffin deposits were formed from heptane-wax solutions on the same stainless steel specimens. These deposits definitely adhered to the surface. Presence of an adsorbed crude oil film on the metal surface increased its free surface energy and resulted in increased deposition of paraffin. The addition to the heptane - wax solution of small amounts of the same distillation residua that were used to form the adsorbed films resulted in decreased cohesive strength in the deposits formed, which resulted in decreased deposition. The presence of a crude oil fraction both in the solution and as a preadsorbed film eliminated the adherence of a deposit of any kind. A mechanism of deposition is proposed which explains the results obtained. INTRODUCTION The natural formation of any predominantly organic accumulation in oilwell tubing, surface flow lines or other production and storage facilities is called a paraffin deposit. These deposits restrict the production of crude oil, causing a substantial increase in production costs because of decreased flow capacity, expense for periodic deposit removal and unproductive downtime. The conditions under which such deposits form, their physical characteristics and the nature and severity of the problem created are extremely varied. Over the past several years, much progress has been made in developing and utilizing methods to remove accumulated paraffin deposition. However, like so many other problems, the basic stumbling block appears to be a lack of understanding of the fundamental mechanism involved in the formation of such deposits. Crude petroleum is known to contain considerable quantities of polar, surface active substances which Doddl has shown to be present at the oil-water interface. Denekas, Mattax and Davis2 observed that the wettability of reservoir rocks was drastically altered by exposure to crude oil fractions; and Zisman, et a1.3 showed that the nature of the compounds adsorbed on a surface would determine its wettability characteristics. Cole and Jessen4 and Ehrig5showed that surface wettability can have a profound effect on the magnitude of paraffin deposition, and Parks6 demonstrated chat the presence of certain adsorbed films on a metal surface would reduce the adherence of paraffin to that surface. Zisman7 has since advanced the theory that the conditions for adhesion are the same as for wetting. Therefore, it was felt that there was adequate evidence to support the supposition that adsorption of compounds from a crude oil might play an important part in paraffin deposition. ADSORPTION-WETTABILITY EXPERIMENTS Initial experiments were conducted to determine the effects of adsorption from solution of crude oil residua on the wettability of a polished stainless steel surface. Distillation residua with initial atmospheric boiling points of 700F were used in preference to the whole crudes in order to concentrate on the molecular weight range of interest, and to eliminate the possibility of composition change due to evaporation of the light ends. Also, these high boiling materials would be expected to be adsorbed from the whole oil in preference to similar compounds of lower molecular weight.

Jan 1, 1966

By I. W. L. Finlay, H. R. Ogden, R. Jaffee, D. J. Maykuth

Aluminum has been found to be soluble in a titanium to about 26 pct, and to raise the temperature range of transformation from a to 8. Two intermediate phoses exist in the system, a new face-centered tetragonal phase, designated as 7, which occurs between 34 and 46 pct Al, and TiAI Metallographic and X-ray diffraction data were used to determine the diagram. ALUMINUM is one of the useful alloying additions for titanium-base alloys. It is an important constituent in two commercial alloys released in 1950, one containing 4 pct A1 and 4 pct Mn, and the other containing 3 pct A1 and 5 pct Cr as the metallic alloy content. It is probable that, in the future, other titanium alloys containing aluminum will be released. In the course of alloy development work, some of the features of the constitution of titanium-rich Ti-A1 alloys have been developed. These are described in the present paper. The only available information on the Ti-A1 system concerns the aluminum-rich end of the diagram. In summarizing the early work, Hansen' indicated that there is little solubility of titanium in aluminum, and that a two-phase region exists up to the intermediate compound, TiA1a (37.2 wt pct Ti), which has a congruent melting point at 1355°C. Fink' has reported that a peritectic reaction occurs at 665°C between the melt and TiA1³ to form the terminal solid solution of titanium in aluminum. The solubility of titanium in aluminum has been established at 0.24 pct at 510°C and is estimated to be between 1 and 1.5 pct at the peritectic temperature. No information has been published on the diagram above TiAl,, other than a statement- hat aluminum raises the a to ß transformation temperature of titanium. Materials and Preparation of Alloys Iodide-type titanium and high-purity aluminum were used in this investigation. Typical analyses of these materials are given in Table 1. Alloys were prepared by arc melting on a water-cooled copper hearth, using the techniques described previously for contamination-free melting.' Weight losses during melting were very low, ranging from 0 to 0.02 g in a 10 to 15 g charge, indicating that little or no loss of aluminum occurred during melting. This permitted the use of nominal compositions for these alloys. Alloy ingots containing from 0 to 7.5 pct A1 were rolled in air at 850°C to 0.040 in. sheet. Alloys containing from 7.5 to 16 pct A1 could only be rolled about 25 pct reduction at temperatures up to and including 1200°C. Alloys containing above 16 pct A1

Jan 1, 1952

By Nestor Torres-Acuña, Fathi Habashi

Metallic copper of purity equal to commercial electrolytic copper is deposited during the anodic dissolution of technically available white metal, Cu2S, in m acidic solution of' copper(II) sulfate as electrolyte and copper sheets as cathodes. The process may be applied on commercial scale since it has the advantage of by passing the converting and poling steps, decreasing pollution problems due to SO, and recovering the sulfur of the white metal in the elemental form. The anodic dissolution is believed to take place in three steps: The working conditions that lead to 98 pct cathodic current efficiency are: 30 gpl Cu2+ and 100 gpl H2SO4 in electrolyte, current density 1.0 amp per sq dm, and tetnperature of bath 40°C'. DURING the smelting of copper, nickel, lead, and zinc sulfide ores, large amounts of sulfur dioxide are produced. Because the release of this gas in the atmosphere causes pollution problems, many attempts were made in the past for its recovery either in liquified form or processed to sulfuric acid. Although these two forms of sulfur are the usual forms that are consumed by the chemical and metallurgical industries, their storage and transport usually raise economic problems. It was realized, long ago, that a process by which sulfur can be recovered directly in the elemental form would be most attractive. Elemental sulfur is easily stored and transported, and is readily converted to SO2, H2S, or H2SO4 when needed. Processes aimed to recover the metals from their sulfide ores, and at the same time by-product sulfur in the elemental form, were recently reviewed.' As early as 1882, Marchese2 patented a process in which a matte having the composition: Cu 15, Pb 14, Fe 41, and S 25 pct was electrolyzed. According to cohen3 the process was applied on a pilot scale by the Aktiengesellschaft fur Bergbau-, Blei-, und Zinkhiitten-betriebe at Stolberg, Rheinland, Germany. The process was unsuccessful, however, owing to the contamination of the electrolyte during electrolysis. Studies in this field were reported by Bernfeld4 and Egli.5 Borchers et a1.6-8 developed the process further by using white metal (Cu 78.2 pct, S 19.6 pct) instead of the matte, and a pilot plant was operated by the Mansfeldschen Kupferschiefer Co. at Eisleben, German~.~ It appears, however, that the process never went into commercial operation. Further studies in this direction were carried out by Russian workers.10-23 The International Nickel Co. of Canada erected a pilot plant at Port Colborne in 1951 to apply the process to nickel matte which is essentially pure nickel sulfide."'- 26 Full-scale plant went into operation at the Thompson Refinery in Manitoba in 1964.27 In this method nickel sulfide matte is melted and cast into anodes analyzing 76 pct Ni and 20 pct S with small amounts of copper, cobalt, and iron. These anodes are then electrolyzed in an aqueous solution of NiS04 at pH 4. Further work on this method was reported in the literature.28-31 In this paper, experiments on the anodic dissolution of white metal in aqueous copper sulfate solution are reported. EXPERIMENTAL White metal, Table I, obtained from The Anaconda Co., was cast in form of anodes 10 by 7.5 by 1 cm, Fig. 1. The anodes are mechanically strong and do not break easily; when polished they gave a shiny gray metallic appearance. From the chemical composition shown in Table I, it can be seen that the atomic ratio Cu:S corresponds approximately to the formula CU2.06S. The copper in excess to the formula Cu2S is most probably present as a separate phase since metallic copper could be seen under the microscope, Fig. 2. Fig. 3 shows the X-ray diffraction pattern of white metal which matches fairly well with that of reagent-grade Cu2S.

Jan 1, 1969

By B. M. Larsen

Jan 1, 1948

By B. M. Larsen

Jan 1, 1948

By R. K. McGeary, B. Lustman

Orientation relationships and rates of annealing of 97 pct cold rolled zirconium have been studied by X-ray techniques, metallography, and by hardness measurements. The process of annealing occurring by the formation of domains, and their subsequent growth without recrystallization, is demonstrated. NUMEROUS investigators1-' have revealed sub-grain formation after annealing cold worked metal single crystals and have generally described the results in terms of a dislocation mechanism of polygonization.5,6 in heavily cold rolled polycrystal-line aluminum the first stages of heating cause an apparently spontaneous subdivision of regions of the deformed matrix into a great number of slightly disoriented domains followed or accompanied by rapid growth of certain domains to form a recrystallization texture.7,8 In the present investigation the isothermal rate of annealing of cold worked polycrystalline zirconium has been studied by X-ray techniques, metallography, and by hardness measurement. It will be shown that, rather than by the usual nucleation and growth mechanism,"12 the process of annealing can best be explained by the formation of domains early in the annealing treatment and the subsequent growth of these domains without recrystallization. Experimental Procedure All the experimental work was performed on an arc-melted ingot of high purity zirconium crystal bar made by Westinghouse in a production scale deBoer unit. The weight percentage of impurities in the zirconium were as follows: C, 0.04; Fe, 0.05; Hf, 0.014; W, 0.01; Ti, Ni, and Al, 0.003; Si and N, 0.002; Cr and Cu, 0.001. Metallographically the zirconium showed only a single phase. The 4 in. diarn ingot was forged at 760°C to a 1 1/2x3 in. plate and was then rolled at 760°C to 0.150 in. thickness and annealed at this temperature for 20 min to produce an equiaxed grain structure of about 0.1 mm average grain diameter. The hot rolled plate was roller-leveled, surface ground to 0.135 in., cold rolled 83 pct reduction in thickness on a two-high mill, and then to a total reduction of 97 pct on a Sendzimir mill. The 0.004 in. strip material so produced received no subsequent mechanical treatment. Specimens % in. square were sheared from the rolled strip and isothermally annealed at 104 mm Hg in an all glass vacuum system equipped with a Vycor furnace tube. The temperature data presented are the average temperatures during the runs and did not vary more than about k3"C. X-ray Diffraction Methods: When zirconium is drastically cold rolled, a high degree of preferred orientation results in which prism poles, {1010}, are perpendicular to the rolling direction. After fully annealing this material an entirely new texture develops which corresponds to a 20" or 40" rotation of the deformation texture about hexagonal axes of

Jan 1, 1954

By Leo Tarasov

MAGNETIC torque studies of ferromagnetic single crystals have been carried out in a number of laboratories during the last decade1,2 and some work has been reported on polycrystalline material showing preferred orientation. Goss3 used the method extensively in developing electrical sheet with desirable magnetic properties, but he used it as a control rather than as a means of studying the texture. Bozorth4 made a quantitative correlation of a torque curve he obtained from some cold-rolled iron with the texture as determined from X-rays, but did not extend his studies beyond the one specimen. Other studies, which have been reported from time to time 1.5 have also been incomplete in the sense that no effort was made to study a whole series of samples, differing only in degree of cold reduction, or in the annealing temperature, in order to ascertain the effect of such treatments on the texture as revealed by torque measurements. It is the purpose of this investigation to make such a study, mainly in order to see how useful the method can be made when used under favorable circumstances and to find what kind of a correlation can be expected between magnetic and X-ray studies of texture. Before proceeding further, it is desirable to say a little about single crystals, so as to make clear the concepts involved in magnetic torque measurements.

Jan 1, 1939

By J. C. Bradley

THE relation of annealing temperature to conductivity of copper wire has been determined.1 Conductivity hard was 98.26 per cent. After a 10-min. heating at 200° C. it was 98.69. By annealing 10 min. at 300° C. a large increase, to 100.93, occurred. Maximum conductivity, 101.15, was attained after a 500° C. anneal; thereafter it decreased to 100.53 after a 950° C. anneal. If copper is gassed the decrease is much more than this. MATERIAL AND METHOD The work was done on high grade electrolytic copper, 99.942 per cent. copper-plus silver, silver 0.0008 per cent. It was hot-rolled to 3 in., then cold drawn to 0.080 in. The wire was cut into 25 5-ft. lengths and numbered 1 to 25 as cut. Four samples were tested hard. The others were wound into 5-in. diameter coils. For the 100° C. heating a coil was put into water, the water brought to boiling, and the wire kept at this temperature for 10 min. For the higher temperatures the coils were placed in envelopes of sheet copper, a little water added, and the envelopes sealed by folding over the edges twice, and hammering them together. This kept the air out very well. The envelope and wire were brought to the desired temperature; this was maintained for 10 min., then the whole was water-quenched.

Jan 1, 1927

By Edwin Hopkins

THE year 1923 started a few days after the Venezuelan Oil Concessions, Ltd., discovered a 140,000-bbl. well at. La Rosa and a well of between 2500 and 5000 bbl. at La Paz, on the opposite side of Lake Maracaibo. These nearly simultaneous events changed, overnight, the general aspect of oil affairs in Venezuela. Up to that time, big things had been expected by the companies then in the district, but many major companies had shown little interest in the country. Within a few weeks the Pure Oil. Co. and the Gulf Oil Corpn. entered the field and acquired large properties. The Texas Co. purchased several concessions and the Standard of California, Atlantic Refining Co., and Mexican Petroleum Co. established offices. Representatives of many other companies visited the district during the first few months of the year. The sudden influx of buyers naturally caused a great rise in prices and this, together with overproduction in the United States, doubtless caused the slowing up of concession transfers in the latter part of the year. The following property transfers occurred: (1) The Gulf Oil Corpn. contract with the Maracaibo Oil Exploration Corpn., whereby the Gulf acquired the right to select 100,000 acres from the Maracaibo's zones. (2) The Gulf Co. purchase of one-quarter interest in seven concessions of the New England Oil Corpn., Ltd. (3) The Gulf Oil Corpn. purchase of several concessions of Kunhardt and others in the Perija district. (4) The Gulf Oil Corpn. purchase of certain portions of the one-kilometer Lake zone that were not covered by parcels or Government reserves (namely the "sobrantes"). (5) Pure Oil Co. purchase of all Government reserves turned back by Maracaibo Oil Exploration Corpn. in the districts of Mara and Miranda. (6) Standard Oil Co.: of New Jersey deal with the British Controlled Oilfields, Ltd., for control of approxi-mately the eastern third of the .district of Buchivacoa, state of Falcon. (7) Royal Dutch deal with the British Controlled Oilfields, Ltd., for the control of the central third of the district of Buchivacoa, Falcon. (8) The Texas Co. purchase of several concessions in Perija and one west of Mene Grande on the east side of Lake Maracaibo. (9) Purchase by the British Equatorial Oil Co., Ltd., of Goverment reserves corresponding to certain Creole Syndicate parcels under the margin of Lake Maracaibo near La Paz. (10) The Lago Petroleum Co. acquired a concession on all of Lake Maracaibo except a 1-Km. strip along the shore.

Jan 3, 1924

AlFred JamEs," London, Eug.:—I thank you, gentlemen, for Sour kind invitation to address you. It is a very great pleasure for me to be here at your annual meeting, and, although I have been a member since 1894, this is the first opportunity I have

Jan 1, 1909

By L. W. Fagg

The purpose of this paper is to present in a convenient form data and examples necessary in making dynamometer card analyses; also to outline a procedure of well weighing. Many articles and papers have been written delving into the mathematical considerations relative to the shape and characteristics of dynamometer cards. However. it is recognized that there are too many unknown factors involved in such calculations to assure a workable degree of accuracy. For this reason the accepted procedure is to take dynamometer cards on wells in question rather than try to calculate the load curve. The polished rod dynamometer is now recognized as a necessary tool for measuring loads, torque, and horsepower. It is also used to determine pump action and trouble-shoot for any seemingly abnormal pumping condition. The apparently infinite variety of a = maximum load (height x scale constant) b = minimum load. Range of load is difference between maximum and minimum load speed—taken with stop watch stroke —measured at polished rod c = beginning of down stroke in direction of arrow. (End of up stroke) d = beginning of up stroke. (End of down stroke). Polished Rod Horsepower = (Area of card) x Scale const. x Stroke x Length x spm (Length of card) 33000x 12 1.35 1.35------x5300x 24 x 12 2.53 --------------------------= 2.06 23000x12 Appraximate Peak Torque: Upstroke = (2390) (12) (1) = 28,700 in. Ib Downstroke = (1 860) (12) (.866) = 19,300 in. Ib Counterbalance should be increased to make up stroke and down stroke peak torque equal. FIG. 1 dynamometer cards that can be obtained is one reason for the general lack of usage of the dynamometer as a control instrument rather than a means for making routine measurements of leads and horsepower. When it is considered that the dynamometer card is a record of the resultant of all forces acting on the polished rod at any particular instant during the pumping stroke. the problem is then one of breaking down this resultant into its various components. As a means of a quick review we shall consider the examples shown in Figs. 1 to 9: and Tables I and II and then proceed to the interpretation of variously shaped cards caused by some abnormal operating condition. In Table 11, when we were considering the factors involved in calculating the peak polished rod load, it can be seen that the factors involved greatly oversimplify the problem. Certain assumptions are made which may or may not he even close to the actual field conditions, such as the specific gravity of the fluid generally considered as one; that the crank has constant angular velocity; that the down-hole friction is zero; and that the fluid lift is from the pump. In the following examples we shall see what a variation in fluid weight and friction can do to the general shape and magnitude of the dynamometer card. (Figs. 10 to 22.) MAKING THE WELL STUDY It is obvious that it would be impractical to consider in detail all of these factors each time a well study is made, inasmuch as each well study job could conceivably be extended into a research project rather than serve the practical requirements of finding the answer to a specific problem. For this reason it is important that some objective be established previous to the time the well study is made. Load at TU = 3070 Ib Crank angle when polished rod is at position TU = ? ? = 30° Maximum counterbalance effect at polished rod = 2760 Ib Torque at TU = (Load at TU — Max. counterbalance effect-lbs) sin 0 x Length of Stroke 2 = (3070-2760) .5 x 24 = 1860 in. 15 2 Torque at TD = (Load at TD — Max. counterbalance effect-lbs) sin ? x Length of Stroke 2 = (530 - 2760) sin 330' x 24 = 13,400 in. Ib 2 Note: sin 0 from c to d on UPSTROKE will be positive value. sin 0 from c to d on DOWNSTROKE will be negative value Torque at c and d is zero because 0 is zero. FIG. 2 —APPROXIMATE METHOD FOR CALCUlATlNG TORQUE

Jan 1, 1950

By R. W. Raymond

It is impracticable to prepare for the present number of the Bi-Monthly Bulletin a detailed account of the memorable Joint Meeting of the Iron and Steel Institute and our Institute, held in London, the last week in July, and of the, innumerable festivities, entertainments and excursions which accompanied and followed it, in England, Scotland, Wales and Germany. This preliminary sketch, from which all " useful particulars "' have been carefully omitted, is published unofficially, as a convenient answer to the manifold inquiries of members who did not go, and who are now trying to alleviate their unavailing regret by indulging their curiosity. Perhaps they secretly hope to hear that they did not lose so very much, after all-that the affair was not all that could have been desired or dreamed; that there were serious drawbacks, shortcomings and disappointments; and that it is just as well to have stayed it home, and now to hear about it. Let them lay no such flattering unction to their souls. The month they have missed would have been the time of their lives. They will never, never know how good a time it was, or adequately repent of their folly, if they could have gone with us, and voluntarily did not go of course, those who would but could not, have our immeasurable pity, without blame. I shall present here no consecutive and minute story, but only a series of general paragraphs concerning different aspects and stages of our experience. THE WEATHER. The proverbial good fortune of the Institute attended its visiting members and guests at every stage of the late London meeting and the numerous excursions which accompanied or followed it. Even the process of crossing the Atlantic was made delightful by smooth seas, through which the great modern transatlantic liners made their way without disagreeable

Sep 1, 1906

By C. E. Coleman, D. Hardie, A. E. Wraith

A photoguaplric method of measuring crack velocities has been applied to an examilzation of- the effect of hydrogen on the impact properties of zirconium. Results indicate that the crack in hydrided zirconit travels at about 26 m per sec whereas that in the uacuum -annealed is dependent on the speed of the hammer. RECENT work on the effect of hydrogen on zirconium reveals that when hydrided zirconium is tested in slow bending the crack producing failure can be unstable. The mode of fracture seems to involve the crack linking up broken hydrides by a ductile mechanism in the zirconium matrix.2" In order to compare the fracture of zirconium with that of other metals which show unstable crack propagation, notably steel, the rate of the crack spread must be known. As the methods previously used for measuring crack growth are either unsuitable for the present work5-'' or very costly," a simple technique has been devised in which the maximum crack velocity is derived from a series of crack position-time measurements. EXPERIMENTAL PROCEDURE The experimental arrangement is shown schematically in Fig. 1. The flash unit12 was triggered when the Charpy hammer touched the specimen and the 6-psec flash of the lamp delayed by a preselected time interval in the range 100psec to 10 msec. The camera was left on open shutter during the test. From direct measurement on a calibrated photographic print, Fig. 2, the position of the crack and the specimen was found at a known time after impact and, from a series of such tests using an appropriate range of flash-delay times, the crack velocity was estimated. Preliminary experiments were carried out on mild steel above and below its transition temperature. Vacuum-annealed zirconium, and zirconium hydrided to 100 ppm H were then tested at 20" and 150°C. For comparison, Zr-2.6 pct Nb alloy (in the 0 + transformed /3 condition), vacuum-annealed or hydrided to 100 ppm H, was tested at 20 C. The chemical analyses of these materials are given in Table I. For the high-temperature tests a fine chromel-alumel thermocouple was spot-welded onto each specimen close to the notch. The test piece was heated up to 200°C to allow enough time for preparing the apparatus while the specimen cooled to the testing tem- perature. It was assumed that the specimen cooled uniformly. The accuracy of the flash-delay time was better than i2 pct i 5 psec. The crack length was taken as its maximum distance traveled normal to the length axis of the specimen. Errors in these measurements arise as a result of the uncertainty in the location of the crack tip and the difficulty in defining the exact position of the crack starting point. The latter was due to the bonding and large amounts of deformation at the hammer contact point, especially in the vacuum-annealed specimens tested at 150°C. The maximum error in the measurements was however estimated to be about 5 pct. DISCUSSION OF RESULTS From the trial experiments using mild steel above its transition temperature it can be seen from the plot of crack length against time after impact, Fig. 3. that a reasonable estimate of the maximum crack velocity at the surface of the specimen may be made. Other features of note are the initiation time before the crack is first seen and the slowing down period

Jan 1, 1967

By F. E. Bash

Previous to the war, this country depended on Europe for its supply of a number of alloys of great importance in the manufacture of electrical apparatus and equipment. When this source was cut off shortly after the beginning of hostilities and the small stocks in the United States were exhausted, either inferior substitutes had to be used or the manufacture of the apparatus suspended. Since electrical equipment was of primary importance in the prosecution of the war, the substitutes had to be used until the composition and processes of manufacture of the alloys could be determined. Included among these alloys was one generally known as manganin, which is composed chiefly of copper and manganese and which, beside having a low-temperature coefficient of resistance, has a low thermal electromotive force against copper. These qualities make it valuable for the manufacture of electrical instruments and machines in which it is used in the shape of wire, rod, and strip. As a result of these circumstances, an investigation was started to determine how manganin could be made on a commercial basis so that a product of uniform quality and the necessary electrical characteristics could be produced. The object was to procure an alloy with temperature coefficient of resistance not greater than 1 X 1X per " C. and a thermal e.m.f. against copper no greater than that of the imported material. It is characteristic of manganin that the temperature-resistance curve is not a straight line but has a peak, which varies in position with different samples; it is most desirable, however, to have it at a temperature of 25' C. if possible. The coefficients of manganin from all records available ranged from a large negative to a large positive value. The composition as reported by different authorities is given in Table I. Prof. Matthew A. Hunter, of Rensselaer Polytechnic Institute, made up a number of small melts of manganin in a graphite crucible and the one that he reported as having the best cocfficient gave the following analysis: Copper, 83.6 per cent.; nickel 2.5 per cent.; manganese, 13.6 per cent.; iron, 0.3 per cent. An analysis of a sample of German manganin gave the following: Copper, 82.6 per cent.; nickel, 3.8 pcr cent.; manganese, 12.8 per cent.; iron 0.7 per cent.

Jan 1, 1921

By Nicholas J. Grant, Irmgard Rump, Bill C. Giessen

The system W-Hf was determined by use of metal -lographic and X-ray methods. The only interrnetal-lie phase W2Hf melts peritectically at 2650° ± 50°C. A eutectic between W2Hf and ß-Hf solid solution exists at 78 at. pct Hf arul 1930º ± 10°C. The addition of tungsten loulers the hafnium transfornzation; there is a eutectoid at 93 at. pct Hf and 1560°C. The solubility limits of the terminal solid solutions were determined. At the beginning of this investigation, the system had not been elaborated; only crystallographic work had been done to determine the structure of the occurring intermetallic compound W2Hf, and a certain analogy to the system W-Zr was to be expected. Special emphasis was placed in this program on the Hf-rich part of the diagram. Following the completion of our experiments, a phase diagram was suggested by Braun and RUdY.1 EXPERIMENTAL METHODS The investigation utilized tungsten powder supplied by the General Electric Co. with a purity of about 99.9 pct and hafnium crystal bar of about 97.7 pct purity, 2.3 pct Zr, supplied by Foote Mineral Co. Typical analyses are given in Table I. The procedures followed were identical with the ones described for the Re-Nb diagram.' Tungsten powder was compacted at 16,000 psi and the necessary amount of hafnium was added in the form of small pieces cut from the crystal bar, with a reasonable excess of tungsten powder to make up for powder losses on melting. High hafnium or tungsten melts were prepared from premelted tungsten and hafnium or by employing master alloys. The melting was done in a Heraeus arc-furnace under argon. Melting and remelting up to 8 times resulted in fairly homogeneous alloys. No weight

Jan 1, 1962

THE purpose of this chapter is to present a general outline of the basic open-hearth process for the benefit of students, practicing open-hearth operators, and metallurgists who wish to review the subject. The discussion is limited to a description of the sequence and purpose of the operations, illustrated by data and examples. Subsequent chapters deal with more detailed and fundamental studies of the subject. The function of the basic open-hearth furnace is to convert various types of ferrous material into finished steel of given com- position and quality. In comparison with other steelmaking methods, the basic open-hearth process is one of the most versa- tile, both from the standpoint of the raw materials that can be used and the types of steel that can be produced. The process can be considered as a sequence involving melting, refining, and deoxidation. With some types of liquid-metal charges, the melting stage is not present, but refining and deoxidation in varying degrees are fundamental features of the process. GENERAL DISCUSSION OF BASIC OPEN-HEARTH PROCESS The first consideration in open-hearth practice is the type of charge on which the operation is based. This consists of three components-fluxing, oxidizing, and metallic materials. Fluxes. In the basic process the fluxing material is primarily lime, added in the form of either limestone (CaC03) or burnt lime (CaO) . This is supplemented by magnesia (MgO) and lime from the furnace bottom and banks. The function of these fluxes is to form a slag with the silica (SiO2) , manganese oxide (MnO), iron oxides (FeO and Fe203), and phosphorus oxide (P205) that are produced by the oxidation of varying amounts of the silicon, manganese, iron, and phosphorus in the charge during melting and refining. The slag, composed of the basic fluxes and the neutral and acid oxides, floats on top of the steel bath when the charge is melted. The composition of this slag depends on the amount of each slag-forming element present in the charge and on the extent of oxidation of these elements during the course

Jan 1, 1964

TO THE BOARD OF DIRECTORS, AMERICAN INSTITUTE OF MINING AND METALLURGICAL ENGINEERS: Gentlemen.-I have the honor to present the following report of the President for the year 1919. In order that this report may be printed and distributed to the members in advance of the February meeting, it is necessary that it end with the calendar year 1919. Any activities during the first six weeks of 1920 will be covered in the Secretary's report for the year 1920. VISITS TO MEMBERS Your President has visited each of the Local Sections of the Institute, with the exception of the ones at Washington, D. C., Tulsa, Okla., and the Nevada Section. These three sections have not arranged meetings at which the President could be present. In addition, your President, accompanied by President Jennings and Secretary Stoughton, in the year 1918, attended meetings of members in Minneapolis and Duluth, Minn., and Houghton, Mich. A dinner and meeting of the members in Pitts-burgh, Pa., was also attended, in company with the Secretary and your President also attended the meeting of Canadian Mining Institute in Montreal, in March, 1919.

Jan 2, 1920